As the Senate debates this week immigration policy and border security, Sen. Jeff Flake plans to file legislation that would provide a 12-year path to citizenship for "dreamers" and the $25 billion that President Donald Trump wants for a border-wall system, while maintaining current legal immigration levels.

The debate will determine which competing plan — if any — can secure the 60 votes needed to clear the Senate's procedural filibuster.

Flake's bill has one key difference

The major difference between Flake's proposal and the Secure and Succeed Act is that Flake's legislation wouldn't cut overall legal immigration levels.

Flake has argued that legal immigrant labor is crucial to U.S. economic growth, last month saying on the Senate floor that he was troubled that the proposed changes to legal immigration "would come just as the aging U.S. population increases our dependence on a growing workforce."

Flake would offer a 12-year path to citizenship to 1.8 million "dreamers," or undocumented immigrants who were brought into the United States as children. Dreamers who are now participating in DACA, which Trump is trying to eliminate on March 5, would get a two-year credit. The program was created by then-President Barack Obama via executive action to shield the young immigrants from deportation and allow them to get work permits.

To be eligible for the Flake bill's path to citizenship, a dreamer would have had to have been younger than 18 when he or she arrived in the United States and have lived here continuously since before June 15, 2012. He or she must be attending college, have a high-school or equivalent diploma or have military experience. The dreamer can not have any criminal convictions or moral violations and must have addressed any tax liability.

The PILLAR, or Preserving Immigration Levels and Legally Enhancing Readiness Act, also would eliminate the Diversity Immigrant Visa Program, which Trump also wants to do, and would reallocate 25,000 of the program's roughly 55,000 visas to employment-based immigrants and the other 25,000 to help eliminate the backlog in family-sponsored immigration.

In contrast, the Grassley bill would cut the diversity and family-unification visas and initially use them to clear the existing visa backlogs. But after that, the visas would appear to end.

Flake's bill also would, according to a summary obtained Monday by The Arizona Republic, restrict family-based immigrant visas to the spouses and children of the sponsoring immigrants. But it would reallocate the visas to relieve the existing backlog and then provide 50 percent of the remaining visas to immigrants with advanced degrees and the other 50 percent to skilled workers.

Even before this week's debate, Flake raised the possibility of Congress being unable to find consensus on the immigration issues.